Waterproofing ICF Foundations

A peel-and-stick membrane along with good perimeter drainage will keep the basement dry

Whenever possible, I persuade
my customers to
use insulating concrete
forms (ICFs) for their
foundations — particularly if they
intend to use the basement as a finished
living space. I like ICFs because they can
be assembled by the on-site crew, there
are no heavy forms to haul and set, and
rebar is easy to place. ICFs also have a
high built-in insulating value and,
unlike retrofitted rigid foam board, they
align with the framing above.
Membrane System
As with a conventional basement
foundation, ICFs must be waterproofed
below grade. Because of the joints
between the blocks, foam forms alone
won't prevent water penetration. In the
past, I've used Tuff 'n' Dri, a dealerapplied
spray-on elastomeric coating
that cures very quickly.